Printing-plate matrix and method of making same



E. E. NOVOTNY.

PRINTING PLATE MATRIX AND METHOD 0F MAKING SAME.

APPLICATION min Duma. Isls.

1,398, 14 Patend Nov. 22, 1921.

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EMIL E. NOVOTNY, OF LOGAN, PENNSYLVANIA, ASSIGNOR TO JOHN STOGDELL STOXES, OF PHILADELPHIA, PENNSYLVANIA.

PRINTING-PLATE MATRIX AND METHOD OF MAKING- SAME.

Specication of Letters Patent.

Patented Nov. 22, 1921.

Application led December 18, 1919. Serial No. 345,809.

K citizen of the United States, and resident of Logan, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Printing-Plate Matrices and Methods of Making Same, of which the following is ,a specification.

This invention relates to a printing plate matrix and method of making the same, and has particular application to a, matrix adapted for the molding of printing plates made in Whole or in part from plastic or cementitious materials, especially such synthetic resins as bakclite, condensite or other phenolic condensation product.

The use of phenolic condensation products has been found to be particularly advantageous for the production of strong, durable, high grade printing plates and matrices therefor, because this material may be readily molded with the greatest exactitude to produce an article of the desired shape, form and dimension, and during or after the molding operation may, under the action of heat and pressure, or heat pressure and cooling be caused toreact to assume a hardened and set and practically unchangeable condition. However it is ditlicult, es-v pecially in the manufacture or reproduction 0f line Work, where the type or plate constituting the original from which the matrix is made embody small tine type, or intricate designs, to make a matrix-having the phenolic material as an essential constituent, or to make a phenolic plate from such a phenolic matrix, because in making the matrix from the original body of type the phenolic material has a tendency to anchor or stick to the original type body so that it cannot be separated or removed therefrom Without destroying the molding face 'of the matrix, While in attempting to mold a phenolic plate against a phenolic matrix, the atiinity of the phenolic material ot the plate for that of the matrix Will cause the same ditiiculty of sticking or anchoring. resulting in the inability to separate the plate and the matrix Without destroying one or both.

Apart from such disadvantage however these phenolic condensation products form ideal constituents in making matrices and plates because, as is Well known, in modern printing, especially on large jobs, the tendency is tomake a great many plates or replicas of an original, and frequently this original will be a combination of various kinds of type, brass rules, half tones and the like, set up in a printers chase. As the phenolic material is readily molded, it will faithfully reproduce the elevations and depressions, and the details of the original, and the matrix bein made may be molded to `definite dimensions. However in molding the' matrix the material will have a tendency to flow toward or seek points of least resistance, that is'where there is little direct pressure of the material against the original, and will also reproduce any roughness or defect in the original. In makinga phenolic printlng plate against a paper faced matrix there will be reproduced on the face of the plate the slightest roughness, of the matrix face such as that caused by the web or paper finish appearing on the material of the matrix face. I have attempted to remove the anchor points, rough spots and other defects produced on the face of the matrix, and also on the face of the plate by employing high speed buthng tools, but the roughening or other defectusually occurs in such inaccessible places, for example in the space between the type characters that it is commercially impracticable to so remedy the deliciencies. I have also resorted to the use of solvents for eliminating the defects, vbut as these vsolvents will attack the face of the article,

and as the phenolic condensation product of the article has set to a more or less infusible form, this method I have found to be unsatisfactory. i

To obviate defects in the making of a matrix from original type, and the subsequent molding of plates from this matrix I have heretofore faced the matrix body, composed of phenolic material, or phenolic material in combination with other substances, such as fiber, with a layer or sheet of metallic material, such as metal foil. This metal face had reproduced therein the type characters of the original to form the molding face, and this type of matrix has been so satisfactory that I have been able to produce vast quantities of commercially useful phenolic printing plates. yHeretofore, however, I have used a relatively heavy or thick foil for the purpose of getting the necessary surface flow or tension of the foil face to produce the swelled or sticking* or anchoring of the plate and matriirthereby incurrin the disadvantages heretofore mentioned.v have found how ever thatthe use of a heavy foil for facing the matrix is liable under the lmolding pressure to break down or damage line type, liairA line rules, overhung italics and the like. My investigations reveal that the ideal matrix, particularly for fine work with delicate type, should have a f acng in the nature of a layer -of skin like smoothness with rounded or swelled non-printingl parts, and

which could be so treated'that the matrix would not anchor to the original type, nor lthe plate to the matrix.

One of the principal objects of my invention, therefore, is the production of a strong, durable and accurate matrix havin a molding face inthe nature of a han?, smooth, skinlike cementitious substance,

such face being preferably formed from a synthetic resin such as a phenolic condensa- V`:Coil surface.

tion product. If desired, I may cover this face with an exceedingly thin sheet of metal, such as foil. but this is not absolutely nec essary. c

My invention consists in the matrix .and

the method of making the saine set forthv in the falling pended claims.

In the accompanying drawing:

Fig\1i'e'1,.v is a cross sectional view taken through 'the' face section of a blank from which the matrix is to be made.

Fig. 2, is a similar view taken through the backingI section of such a blank.

Fig'.3, is a'cross sectional view showing the face and backing sections assembled in within the scope of the apa press and upon a, body of type, ready for making the matrix, the press and type being. merely conventionallyillustrated.

Fig. 4, is a cross sectional viewftlirough the completed matrix. v

Fig. 5, is a cross sectional'view through a modified form of matrix wherein the face of thematrix is providedwith a metallic Where I herein useV the term lphenolic condensation varnish, 'or phenolic material,` or similar expressions, ,I wish it to be understoodas including t any 'cementitious products possessing the attributes or characteristics heretofore mentioned.

Y Referringnow to Figs. 1 to 4V of the draw- A' A ving, and particularly to Figs.V 1v and the letter A in Fig. 1 indicates as an entirety a blank from which the face section of the matrix is to be made. a sheet 1 of fibrous material, such as chip board orblotting paper,y or other porous4 material which is impregnated, but vnot saturated fully with a p enolic condensation varnish shown ,at 2 the varnish having been dried out in any suitable manner so that the phenolic material, which constitutes about sixty per cent. in weight of the ber This blank includes board, is inl a substantially' non-flowing condition and acts to reinforce and strengthen the ber sheet or board. This impregnated ber sheet is coated on both sides with layers of phenolic material, shown at 3, the material of these coatings 3 comprising a mixture of substantially equal partsof phenolicl v varnish'and lam black, e coatings having also been dried out,- by the elimination ofthe solvent until they are substantiall dry. These coatings 3 are in turn cove with v'coating or layers 4, also of phenolic material, but what-might be called a richer de or mixture, for the coatings 4 may gaof a mixture of four parts of phenolic varnish, one part of lam black, and about one-'half part of a pheno ic solid solvent, or lasticity oil of any well knownl variety. hesc `coatings 4 have also been heated to eliminate the solvents and are in a partially reactedor hardened condition but still capable of being softened and molded under heat and pressure. The coatings 3 are employed between the coatings 4 and the impregnated ber sheet Vto prevent the material of the'coatings 4 from penetrating or soak ing into the ber.- The impregnated ber coated sheet A is squeezed or pressed a inst a polished copper sheet between the p atens of a cold press with a pressure of about two thousand: pounds to the square inch for aboutv one minute to thoroughly compact the various coatings. Then the compacted blank, resting on the copper sheet is placed in a heated press and subjected to a pressure' of about two hundred pounds to a .square inch for about ve minutes at a temperature of about 212 degrees F. to oo nvert the coatings or layers 4 into highly polished,

smooth, skin-like faces. This constitutes the blank shown in Fig. 1.A The backing for the laminations or ber sheets, in the present instance three in`number, shown at 5, 6 and 7,.

which are also impregnated to a. sli. ht de` gree with a phenolic material as in 'cated at 8, the phenolic material at the time of im- 2,

pregnation being in the Inature of a phenolic varnish constituting about twenty r cent.

of the wei ht of the ber, and whic is sul v uently ried out the elimination of the vents so that the' p enohcgum-re'maining so 'is substantially in anon-,flowing condition isc.-

oven and heated at a temperature of about.

250 degreesF. for one hour, to harden and set the phenolic material. This will cause the fiber of the laminated backing to expand somewhat, and it may be subsequently compressed for making the matrix, and due to the phenol impregnated therein will maintain its compressed condition, as will be readily understood.

The face section A and the backing section B may now be cemented to ether by a suitable adhesive to form a sing e blank, or

may be supplied to the matrix maker sepa-l ratel the union taking place in making the matrix. These sheets may be shipped from place to piace, or stored indefinitely, as they are not affected by climatic conditlons.

In making a matrix the original to be reproduced, such as a body of type, etchings, or the like, locked in a chase, and conventionally shown at T, may be placed upon the lower platen of a suitable press P, the platens of the press being hollow so as to be heated and cooled in the usual manner, the press platens being herein merely conventionally shown. The facing section A of the blank is placedwith one of its faces 4 in direct contact with, the type, and upon this section A I may then sprinkle a free-flowing phenolic gum to a thickness of from five to fifteen one thousandths of an inch, as indicated by the numeral 11, in Fig. 3. I then impose the backing section B upon the face section A, and the platens of the press are closed to a ply heat and pressure, the closing of the pl)atens being limited by suitable bearers 12. Ihe press platens are slowly closed against the bearers to allow the sprinkled layer of phenol, shown at 11, to soften and fiow to the elevations or non-printing parts of the matrix, produced in the molding operation. That is to say the phenolic gum flows t'o the points of least ressurewvhich are the unsupported parts o the matrix or the elevations which produce the non-printing portions of the printing plate. The press may be ke tf closed, at atemperature of 212 degrees for a period of from three to fifteen minutes,

depending on the degree of hardness desired .for the matrix and alsol on the quickness with which the phenolic material in the matrix body will set. When the press is opened and the matrix removed from the type 1t willoe found that the original tyne matterhas been accurately reproduced with the greatest detail, and that no difficulty whatever is experienced in removing the matrix from the type, as it will not stick. Indeed, the matrix can be stripped from the type'even whenV the latter contains typev matter having overhung characters and the like. After the matrix has been removed from the typeform against which it has been, molded at the relatively low temperature above mentioned, it is again heated in an oven, or through any other suitable agency, to convert the phenolic material to its final hard and set infusible form, this final heating being accomplished at temperatures ranging from 250 to 300 degrees F. It is to be understood that the matrix Was not subjected, While on the type, to a sufficient high temperature to render the phenolic material infusible, because such high temperature would expand and damage the type. Therefore, the matrix was heated While on the type, at a low temperature, or just suiicient to insure proper impression or molding, and the matrix could be removed Without sticking to the type because of the pre-cooked or skln-like nature of the face 4 in contact with the type, as this face will not soften at this low temperature sufficiently to adhere to the type. 0f course, the final cooking or heating of the matrix at the high temperature gives such matrix its final rigid form.

In Fig. 5, I have shown a slightly modified form of my invention wherein the matrix body which is indicated as an entirety by the letter M, and which is made of the united face sections A', and the back sections B', is faced with a metallic foil F, which is exceedingly thin, preferably of a thickness of about one thousandths of an inch. The backing B is similar to the backing B of Fig. 2, and the face section A is similar to the face section A of Fig. 1, except that in the place of the top layer 4, I substitute a layer composed of one part of phenol gum and four parts of barium sulfate, as shown at 15, to insure that the foil will adhere to the face section, and at the same time this layer 15 acts to support the foil.

In casting a printing plate against either the matrix shown in Fig. 4, or the foil face the footing or adherence necessary to cause it to stick temporarily to the face of the matrix'in the form of a smooth imperforate layer. In actual use when casting the plate it is only necessary to brush a small quantity of the separating lmedium upon the matrix face and polish it smoothly with a brush so as to form a thin surface coating over A medium.

In making the printing plate the body of the latter may be composed of any suitable phenolic material',4 omaI combination of such material with other substances such as fiber, fiber board and the like. 1 The plate is molded -against the matrix, under heat and pressure, and when the plate is removed from the matrix after the completion of th`e molding and casting operation the graphite coating will be removed from the face of the' matrix, coming away with the plate, so that it 1s, necessary Ato recoat the matrix with the qsenilrating medium for each plate to be made. hlle have herein shown and described the preferred embodiment of my invention I wish it to be understood that I do not confine myself to all the precise details of construction and method herein set forth by way ofillustration, as modification and variatlon may be made witlrout departing from the spirit of the invention or exceeding the scope of the' appended claims.

' What I claim is:

1. A printing plate matrix comprising a body portion, a molding face section thereon, said molding face section including a layer of hard and 'set synthetic resinous material imposed upon the body portion and a skin-like coating of hard and set synthetic.

Q resinous material imposed upon the afore- .tween the skin-like coating and the bod said layer,.said layer forming a barrier beportion to prevent penetration of the mater1al of said coating into the body portion.

2. A printing plate matrix having a molding face embodying a plurality of layers of a henolic condensation sai layers containing a re centage of the phenolic condensation prodproduct, one of atively low per- `uct while another-of said layers contains a relatively high percentage of said product.

v3.. A printing plate matrix comprism a i body -portion of united long liber sheets 1mpregnated to a minimum degree 'with a hard 'and setE synthetic resinous material, said body portion having a molding :face includ- 'ing a plurality of. layers of hard and set synthetic resinous material, said layers differing from each other in relative hardness.

4. A printing plate matrix comprising av body portion of `fibrous lmaterialv impregnated with a hard-and set synthetic resmous cause in y section.

material, a face section comprising a layer of hard and set synthetic resinous material and a separating coating of vcarbonae'eous material `on the molding face.

5. A printin plate matrix comprisin a body portion aving a hard and set s thetic resinous material incor orated therein, a face section for the bo y ortion including a hard and set synthetlc resinous material and a facin therefor composed of a sheet of relativel t in metallic foil.

6. A printing p ate matrix comprising a body portion including a hard and set resinous material, and a face section for the body portion comprising a layer of hard'and set synthetic resinous materlal, a facing of relatively thin metallic foil for said facing and a separating coating including carbonaceous material imposed on the metallic foil facing,

- 7. A printing plate matrix comprising a backing composed of a plurality-of united sheets of fibrous material vimpregnated with a synthetic resin, and a vface section comprising asheet of fibrous material impreg-l nated with a synthetic resin, the fibrous sheet of the face section having at each face a coating containing a relatively low percent-v age -of phenolic material and a second coating containing a relatively highI percentage of henolic material, said face -section being Yumted with the back section.

8. A printing plate matrix comprisinga backing composed `of a plurality ofzunited sheets of iibrous material impregnated with a synthetic resin, and a face sectioncomprising a sheetof fibrous material impregnated lwith a synthetic resin, the fibrous sheet of the face sectio'nhav-ing at each lface a coating containing a relatively low percentage of phenolic material and a second coatin containing a relatively high percentage o phenolic material, said face section being united with the back section, and a surface facing of relatively thin metallic foil for the face 9. The herein described method of making a matrix which consists in impregnating a sheet of fibrous material with a synthetic resinous material, heating the same to dry out the synthetic resinous material, coatingv said im regneated sheet with a plurality of layers o synthetic resinous material, then heating the same to dry said layers, then imosing said 'sheet upon a body of type or the like and sub'ecting the same to lheat and pressure Ato orm the molding face of the matrix, removing'said matrix freni-the type and subse uentlygheating said matrix ata relatively igh temperature to harden and set the synthetic resinous material to its nal infusible form.

Signed at New York cit inthe county of New York and 'State of ew- York, this 6th day of December, A. D. 1919.

EMIL E. NOVOTNY. 

